I will be putting on Bilstein ride height shocks set at 1.75 with gator back flaps. Is it the width of the tire that rubs or the diameter of the tire. These are the size of tires I have found. What one will fit with out rubbing 275/65/20 diameter 34.1" width10.8" or 285/60/20 diameter 33.5" width 11.2" and there is the 305/55/20 diameter 33.2" width 12". I have a KR wheels are stock with a diesel or should I set at the highest setting for the weight of the diesel? Would like a little rake Just trying to get it right. Thanks